FREE Lee Lohmolator for hydraulic engineers

Anyone who specifies hydraulic valves should have a Lohmolator: Lee Products are offering these useful 'slide rule' devices, which can also be used for calculating lohm rates (ie orifice sizes)

Anyone who specifies hydraulic valves should have a Lohmolator and there is no excuse because they are free! Miniature component specialists Lee Products are offering these useful 'slide rule' devices, which can also be used for calculating lohm rates (ie orifice sizes).

For applications or calculations where the temperature affects the fluid viscosity, the software for Lohm's law can also be supplied free, by Lee Products on floppy disc.

To receive your free Lohmolator, contact Lee Products in the UK.

***Processingtalk Editors note.

By using Google, the origination of Lohm seems to be from "The Lee Company" in the USA, from whose website www.theleeco.com I am grateful for the explanations given in the following text.

Presumably the volume units quoted are US Gallons, rather than UK gallons.

* Lohm Laws for Liquids - how to calculate flow resistance for liquids (a simplified system of defining fluid resistance).

Over the years, The Lee Company has developed the Lohm system for defining and measuring resistance to fluid flow.

Just as the "ohm" defines electrical resistance, the "Lohm" or "liquid ohm" can be used as a measure of fluid resistance.

The Lohm is defined such that 1 Lohm will flow 100 gallons per minute of water with a pressure drop of 25 psi at a temperature of 80F.

Since resistance is inversely proportional to flow, the definition is as follows.

Lohms = 100/(Flowrate, expressed in GPM of water, with a 25psid pressure drop).

So a 1000 Lohms resistance would allow a flow of 0.1 GPM, or 378.5 mL/min.

And a high resistance of 378,500 Lohms allows a flow of only 1 mL/min.

By using Lohms, one can specify performance without concern for coefficients for discharge, passageway geometrics, physical dimensions or tolerances.

The resistance of any flow can be expressed in Lohms and confirmed by actual flow tests.

Lohm Laws generalise the Lohm definition and allow the system designer to specify Lohm requirements for a particular application based on the desired pressures and flow rates.

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